std::experimental::nullopt (3) - Linux Manuals
std::experimental::nullopt: std::experimental::nullopt
NAME
std::experimental::nullopt - std::experimental::nullopt
Synopsis
Defined in header <experimental/optional>
constexpr nullopt_t nullopt{/*unspecified*/}; (library fundamentals TS)
std::experimental::nullopt is a constant of type std::experimental::nullopt_t that is used to indicate optional type with uninitialized state.
See also
nullopt_t indicator of optional type with uninitialized state
(library fundamentals TS)